The Science Behind Sewer Jetting

Sewer jetting is a powerful technique that uses fluid acceleration and the power of high-pressure jetting to blast away blockages and clean pipes thoroughly. The water pressure dislodges blockages and removes debris from the pipe walls, preventing future issues, ranging from unpleasant odours and slow drainage to sewage backups and potential health hazards.

How Sewer Jetting Works

Commercial sewer jetting machines typically generate water pressures between 1600 and 4,000 psi (110 bar - 260 bar), and water flow rates of between 2.2 gpm and 16 gpm (10 lpm 72 lpm) based on the type of engine and pump. Individual configurations are used to handle different sizes of drainage pipes and sewers, from small domestic pipework to main sewer lines.

Pressure, measured in PSI or BAR, indicates the force with which water is expelled from the jetter's nozzle. A higher PSI/BAR signifies a greater force propelling the water through the nozzle. This forceful water stream is crucial for effectively breaking up and removing tough blockages, such as tree roots, grease buildup, or solid debris, from sewer pipes.

Flow Rate is the amount of water discharged by the jetter per minute and is denoted as GPM (Gallons Per Minute) or LPM (Litres Per Minute). A higher flow rate means more water passing through the sewer pipe to clear the debris that the pressurised water has dislodged.

The interaction between pressure and flow ensures comprehensive cleaning of the entire drain pipe infrastructure. An understanding of how pressure and flow dynamics operate is imperative for maintaining optimal drain functionality and to mitigate against future obstructions.

How Does a Sewer Jetter create high pressure?

The key components of a water jetter include an engine, a pump, a high-pressure hose, and a nozzle. Here's an overview of how a water jetter works:

The establishment of Low and Ultra-Low Emissions Zones in European cities has also influenced the development and adoption of low-emission power sources. For example, the UrbanJet is equipped with an 18.5 kW engine meeting Stage V standards, while the CityJet features a robust 44 kW diesel engine with a diesel particle filter to adhere to Stage V regulations. Petrol-powered jetters have also gained popularity due to new regulations and advancements in smart engines that combine power and fuel efficiency.

Our all-electric machines utilise highly efficient lithium-ion batteries to drive an electric motor and pump. Offering performance comparable to diesel or petrol machines, these jetters produce zero emissions and significantly reduce noise levels compared to traditional diesel or petrol-powered counterparts. This noise reduction is especially crucial for nighttime operations or when working in residential and congested areas.

The engine provides the necessary energy to drive the pump, which is responsible for pressurising the water.

Here's a step-by-step description of the working process:

• Intake Stroke: During the intake stroke, the plungers retract, creating a low-pressure zone within the cylinder. This low-pressure zone causes water to be drawn into the cylinder through an inlet valve. The inlet valve opens due to the reduced pressure, allowing water to fill the cylinder.

• Compression Stroke: As the plungers continue their movement, they begin to compress the water within the cylinder. The inlet valve closes to prevent water from flowing back, and the compressed water is forced out through an outlet valve.

• Outlet Stroke: The outlet valve opens during the outlet stroke, allowing the pressurized water to be expelled from the pump. The three plungers operate in a phased manner, ensuring a continuous and pulsation-free flow of high-pressure water.

• Repetition: The entire cycle repeats rapidly, driven by the power source (an electric motor or an internal combustion engine). This repetitive process generates a consistent and high-pressure stream of water, suitable for various industrial cleaning and cutting applications.

Axial Cam Pumps

This type of pump consists of a series of pistons arranged in a circular pattern around an axle or cam. The pistons are typically mounted at an angle to the axis of rotation, allowing them to reciprocate as the cam rotates. While they are more compact and lightweight than triplex pumps they are less robust and are generally used in lower-pressure applications such as pressure washers.

Cam Rotation: The entire assembly rotates, causing the pistons to go through the intake, compression, and outlet strokes sequentially. The continuous rotation of the cam ensures a steady flow of high-pressure water.

Rioned Machine Operation Specifications

How Jetting Machines Work in Operation

The sewer jetter is connected to a water source, which can be a municipal water supply or a dedicated water tank on the jetter itself. The water source supplies the water that the pump pressurises. The pressurised water is then conveyed through a high-pressure hose from the pump to the nozzle. These hoses are reinforced with materials such as steel to withstand the high pressures involved.

Nozzles

The nozzle is the business end of the water jetter. It's attached to the end of the high-pressure hose and is responsible for shaping and directing the high-pressure water jet. Nozzles come in various designs, including rotating nozzles, fixed nozzles, and specialist nozzles for specific cleaning tasks.